The young Dutch sprinter finished 10th in the sprint behind stage winner Mark Cavendish (Dimension Data) but was confident he would keep the race lead. However, he was soon informed by race officials that he had been penalised 20 seconds for taking a tow in the slipstream of his LottoNL-Jumbo team car with 60km to go following a bike change as the race was splitting into two echelons.
The penalty meant Groenewegen slipped to 42nd in the overall classification, 18 seconds down on Viviani. He kept the lead in the points classification and so pulled on the red jersey but with only two stages left to race his chances of overall success were gone.
Groenewegen tried to ride away from the podium area without speaking to the media but when Cyclingnews asked him to stop and speak, he did.
He sportingly accepted the judge's decision but he was angry that problems with his bike had cost him dearly. He dropped the F-word four times in just four sentences.
"I had problems with my bike, the mechanicals fucked it up for me. I actually think it was a good decision by the judges but it fucked it up for me," he said, unable to hold back his swearing.
"I stayed behind the car because it was really windy and the race was broken into two groups. Then I had a mechanical problem. I think my mechanicals fucked it up for me.
On Thursday, stage 4 finishes with the short but steep climb to the edge of Hatta Dam. Groenewegen was not hoping to win the stage but was confident of limiting his losses and winning the Dubai Tour thanks to the time bonuses he picked up by winning stage 1 and finishing third on stage 2 plus any bonuses he secured during Friday's final flat stage.
"It was my goal to win the Dubai Tour but now it's really difficult. Maybe we'll see on the last day. It's the fault of my mechanics," he said, revealing he had problems with the bottom bracket of both his bikes.
"My second bike was fucked too, that's why I changed it. It was the bottom bracket. It was completely fucked!"
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